Can anyone identify this engine please

[dvmnn]

This car was a pre-owned HPI Trophy, that I expected to have a 3.5 (.21) engine, but on closer inspection most of the 3.5s have a black cooling head where this one is purple which is more in keeping with the 4.6, it is low on power and I want to rebuild it but with what parts?  There are no size markings anywhere on the casings.

[.AJ.]

Looks like one of these 

 

https://www.hpiracing.com/en/part/1406

[dvmnn]

I've looked at all the HPI engines and can't find one that is exactly the same.  If you look closely at mine the crankcase is squarer and has closer finning.

[Ninetiesbeard]

Hpi f4.6 i think, purple head with the domed top, first released with the original savage x IIRC

[Nitroholic]

My guess is it's an older .21 motor fitted with an 'upgrade' HPI pink anodised head. HPI made pink anodised upgrades for a lot of parts so you could make a Savage look hideous....

 

Judging from the general state, the corrosion behind the flywheel, and the overall look, it's probably worn out. Expect the front bearing to be shot and leaking and it's probably seen a fair bit of use. The previous owner also seems to have put hte car away wet...as the steel parts are all corroded.

 

Personally, I would source a replacement motor rather than rebuild it. It's going to probably want a piston, liner and rod....and definitely going to want new bearings